Objective: DNA repair pathways in cells are essential for the maintenance of genome integrity, and for countering the induction of tumorigenesis. Topoisomerase II is a nuclear enzyme that functions during both DNA replication and transcription. The topoisomerase II inhibitor etoposide is an antineoplastic drug that has been used to generate DNA damage and maintain apoptosis. Etoposide blocks cell division by interfering with the topoisomerase II and generates double strand breaks. Application of topoisomerase II inhibitors leads to the formation of double strand breaks that are rapidly repaired following removal of the drug. In the present study, we searched the apoptotic events and early double strand DNA repair process that prevent the apoptotic cell death of L929 fibroblasts in response to treatment with etoposide.